Polyadenylation of ribonucleic acids in mouse L cells infected by encephalomyocarditis virus.

Polyadenylation of cytoplasmic RNAs was investigated in L cells infected with encephalomyocarditis virus. During the early stage of infection, the mean size of newly made poly(A) chains attached to cell mRNAs decreased gradually, in parallel with the shut-off of RNA synthesis. Later on, poly(A) segments, an average of 50 nucleotides long, were associated with viral RNA isolated either from polysomes or whole cytoplasm. These segments seemed to be processed differently in the course of time, and RNA molecules containing short poly(A) tracts (less than 20 bases) were incorporated into the virions.